# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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"""Contains custom parameter initializers."""

import jax
import jax.numpy as jnp

from language.mentionmemory.utils.custom_types import Array, Dtype, InitType, PRNGKey, Shape  # pylint: disable=g-multiple-import


def truncated_normal(stddev: float) -> InitType:
  """Truncated normal initializer."""

  def init(key: PRNGKey, shape: Shape, dtype: Dtype = jnp.float32) -> Array:
    return jax.random.truncated_normal(
        key=key, lower=-2., upper=2., shape=shape, dtype=dtype) * stddev

  return init
